Microsoft won’t admit what the problem is beyond saying customers “may experience difficulties in Microsoft Excel or other applications,”. ‘Difficulties” could mean anything. If an Office 2010 starts having any problem, there’s no way to know if the new patches are the blame or some other bug.

Japanese customers take the hit

Microsoft has withdrawn the patches for all Office 2010 users but the bug seems mostly, if not completely, limited to Japanese language Office 2010. Check out Did2Memo which has some English sections.

Opening an Excel document may hang Excel entirely.

Switching to English language interface for Office 2010 may bypass the problem but the better fix is to uninstall the patches listed above.

Access 2010 had a similar problem in November 2018 when KB 4461522 caused the program to crash. That update was designed to prepare for the same change in Japan.

Why Japan Excel 2010 only?

If we say the Office problem is due to a change of Era, Japanese people will know immediately what we’re talking about. Us mere gaijin need a primer to understand the problem and why it’s not a big concern beyond Japan.

Traditional Japanese dates use an ‘Era’ based on the reign of the Emperor. For example, the Showa era was during the reign of Emperor Hirohito. Western year 1945 is ‘Showa 20’ in Japan.

Currently we’re in the Heisei era of Emperor Akihito. 2018 was ‘Heisei 30’. In Japan both western dates and traditional dates are used, depending on the situation. Office software must deal with both (Office handles many different calendar systems).

The Heisei era ends on 30 April 2019 when the current Emperor intends to abdicate.

1 May 2019 will be the start of a new era. There are complex and somewhat unprecedented handover ceremonies and announcements.

No Era name, yet

Microsoft and other software makers must update to cope with the new era but there’s a problem. Even though we know the name of the new emperor, the new era name has not been announced.

The new era name will be announced on 1 April 2019. Until then, Microsoft has to update software without a key piece of information.

Of course, that’s no excuse for the buggy patch. Excel 2010 crashing should have been caught during testing especially since a related patch to Access 2010 had caused trouble.

Microsoft should be more honest about the problem. Customers would know what to look for and not waste time. Knowing it was a uniquely Japanese problem would reassure the rest of Microsoft’s customers that they are likely unaffected.